To build a stable model rocket that can withstand multiple launches, and launch it to gain a firsthand understanding of kinematics, forces, and vectors.
We did not record as much data for the second launch. Additionally, we were unable to inspect our rocket after the second launch because it landed on the roof of the school (we think.) We do not know whether the parachute deployed since we lost sight of it before the deployment.
Angle of elevation was measured from a point 50.m from the launch site, as illustrated by diagram below.
Height
Since tan(45) = height/baseline
height = baseline * tan(45)
height = 50.m * 1 height = 50.m Average Ascent Velocity
D (height of rocket) = 50.m
T (time up) = 5.76s
V = ?
V = D/T
V = 50.m / 5.76s V = 8.7m/s
Average Descent Velocity D (height of rocket) = 50.m T (time down) = 4.67s V = ?
V = D/T V = 50.m / 4.67s V = 11m/s
Sources of Error
Non-vertical flight of rocket (caused by lateral wind, angle of launch pad into wind.) Invalidates baseline measurement, potentially large effect on calculated maximum height of rocket.
Measurement error: precise point / time of apogee is difficult to determine. Probably minor effects on measured values.
Because our rocket flew in a stable manner, was launched a total of four times (two flight tests, two with the class) without serious damage, and we obtained good data from our testing, this activity was a success for our group despite issues with the recovery system.
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PurposeMaterials
Procedure of Construction
Procedure of Launch
Performance Projections
Data
Analysis
Conclusion
Purpose
To build a stable model rocket that can withstand multiple launches, and launch it to gain a firsthand understanding of kinematics, forces, and vectors.Top of page
Materials
To build the rocket we used:Top of page
Procedure of Construction
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Procedure of Launch
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Performance Projections
Maximum Velocity
M (mass of rocket) = 110g = 0.11kgFa (B6 avg. thrust) = 6N
T (B6 burn time) = 0.85s
V1 = 0
V2 = ?
A = ?
D1 (distance under power) = ?
Fg = MA
Fg = 0.11(9.8)
Fg = 1.1N
Fnet = Fa - Fg
Fnet = 4.9N
F = MA
4.9 = 0.11A
A = 45 m/s^2
V2 = V1 + AT
V2 = 0 + 45(0.85)
V2 = 38 m/s
Maximum velocity of 38 m/s will occur just as the fuel is exhausted.
V2^2 = V1^2 + 2AD
1444 = 0 + 2(45)D1
1444 = 90D1
D1 = 16m
Maximum Altitude
V1 = 38 m/s
V2 = 0
Ag = -9.8 m/s^2
D1 = 16m
D2 (distance coasting) = ?
D (max. altitude) = ?
V2^2 = V1^2 + 2AD
0 = 1444 + 2(-9.8)D2
19.6D2 = 1444
D2 = 74m
D = D1 + D2
D = 90m
Assuming vertical launch and no air resistance, the rocket should achieve a 90m apogee.
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Data
First Launch
Second Launch
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Analysis
Measured Data
Height
Since tan(45) = height/baseline
height = baseline * tan(45)
height = 50.m * 1
height = 50.m
Average Ascent Velocity
D (height of rocket) = 50.m
T (time up) = 5.76s
V = ?
V = D/T
V = 50.m / 5.76s
V = 8.7m/s
Average Descent Velocity
D (height of rocket) = 50.m
T (time down) = 4.67s
V = ?
V = D/T
V = 50.m / 4.67s
V = 11m/s
Sources of Error
Non-vertical flight of rocket (caused by lateral wind, angle of launch pad into wind.) Invalidates baseline measurement, potentially large effect on calculated maximum height of rocket.
Measurement error: precise point / time of apogee is difficult to determine. Probably minor effects on measured values.
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Conclusion
Because our rocket flew in a stable manner, was launched a total of four times (two flight tests, two with the class) without serious damage, and we obtained good data from our testing, this activity was a success for our group despite issues with the recovery system.
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λ - Design - Performance Projections- Materials - Time LinePrimary Launch - Secondary launch - Analysis - ConclusionLab Report